JTableのセルに行選択チェックボックスを追加する

class CheckBoxTable extends JTable {
  private static final int CHECKBOX_COLUMN = 2;
  private transient MouseListener handler;
  private transient ListSelectionListener listener;
  private int checkedIndex = -1;

  protected CheckBoxTable(TableModel model) {
    super(model);
  }

  @Override public void updateUI() {
    addMouseListener(handler);
    getSelectionModel().removeListSelectionListener(listener);
    super.updateUI();
    setSelectionModel(new CheckBoxListSelectionModel());
    handler = new CheckBoxListener();
    addMouseListener(handler);
    listener = e -> {
      if (checkedIndex < 0) { // e.getValueIsAdjusting();
        ListSelectionModel sm = (ListSelectionModel) e.getSource();
        TableModel model = getModel();
        for (int i = 0; i < getRowCount(); i++) {
          model.setValueAt(sm.isSelectedIndex(i), i, CHECKBOX_COLUMN);
        }
      }
    };
    getSelectionModel().addListSelectionListener(listener);
  }

  @Override public Component prepareEditor(
      TableCellEditor editor, int row, int column) {
    Component c = super.prepareEditor(editor, row, column);
    if (c instanceof JCheckBox) {
      JCheckBox b = (JCheckBox) c;
      boolean selected = getSelectionModel().isSelectedIndex(row);
      b.setBackground(
        selected ? getBackground() : getSelectionBackground());
      checkedIndex = row;
    } else {
      checkedIndex = -1;
    }
    return c;
  }

  private final class CheckBoxListSelectionModel
      extends DefaultListSelectionModel {
    @Override public void setSelectionInterval(int anchor, int lead) {
      if (checkedIndex < 0) {
        super.setSelectionInterval(anchor, lead);
      } else {
        EventQueue.invokeLater(() -> {
          if (checkedIndex >= 0
              && lead == anchor
              && checkedIndex == anchor) {
            super.addSelectionInterval(checkedIndex, checkedIndex);
          } else {
            super.setSelectionInterval(anchor, lead);
          }
        });
      }
    }

    @Override public void removeSelectionInterval(
        int index0, int index1) {
      if (checkedIndex < 0) {
        super.removeSelectionInterval(index0, index1);
      } else {
        EventQueue.invokeLater(() ->
          super.removeSelectionInterval(index0, index1));
      }
    }
  }

  private final class CheckBoxListener extends MouseAdapter {
    @Override public void mousePressed(MouseEvent e) {
      JTable table = (JTable) e.getComponent();
      Point pt = e.getPoint();
      if (table.columnAtPoint(pt) == CHECKBOX_COLUMN) {
        int row = table.rowAtPoint(pt);
        checkedIndex = row;
        ListSelectionModel sm = table.getSelectionModel();
        if (sm.isSelectedIndex(row)) {
          sm.removeSelectionInterval(row, row);
        } else {
          sm.addSelectionInterval(row, row);
        }
      } else {
        checkedIndex = -1;
      }
      table.repaint();
    }
  }
}